KENNEDY SPACE CENTER, Florida (CNN) -- NASA said Friday it was going to take immediate action after a report raised safety questions about astronauts drinking before flying missions.
NASA allegedly gave the OK to a drunken astronaut to fly on the shuttle, but liftoff was delayed.
The space agency said astronauts flew drunk at on at least two occasions, despite warnings from doctors and colleagues that they posed a flight risk.
As a result, NASA deputy administrator Shana Dale said new procedures would be put in place immediately, including an internal review and a no-alcohol policy for 12-hours before all missions.
With the next space shuttle mission just two weeks away, Dale said NASA has "already had discussions with the crew commander of next shuttle mission and its flight surgeon." Officials have communicated "the allegations in the report and NASA's expectations of alcohol use and getting into a spacecraft." Watch Dale discuss the troubling report »
Dale said the goal was to insure that the flight surgeon and crew commander know that they are "expected and they are empowered to raise any flight safety issues that they have."
The report was prompted by the arrest of former astronaut Lisa Nowak, who was accused in February of the attempted kidnapping of a romantic rival.
According to the report, released earlier Friday, interviews with flight surgeons and astronauts "identified some episodes of heavy use of alcohol by astronauts in the immediate preflight period."
Dale said the agency would act immediately on reports of alcohol use, conduct an internal safety review and then "recommend corrective actions." NASA takes the report's recommendation for an astronaut code of conduct "very seriously," Dale said.
The committee report offered no specifics about the drinking episodes and said no attempt was made to confirm information given in interviews.
"Until we have more information, NASA cannot determine the veracity of these claims," the report said.
However, Air Force Col. Dr. Richard E. Bachmann, head of NASA's Astronaut Health Care System revealed a few more details of the claims Friday.
"There were two incidents described to us in more detail as more representative of a larger concern," said Bachmann. "One of those incidents involved both the shuttle and the T-38 [NASA jet aircraft] the second incident involved the Soyuz-ISS." Russian Soyuz spacecraft are used to ferry crew members to and from the international space station.
"There were still two incidents but they were structured such so that they involved all three operations," Bachman said, explaining that an astronaut was preparing to launch in a shuttle, but when the mission was delayed, the astronaut was to fly in the T-38.
Panelists looked into NASA's medical and psychological screening process and addressed other behavioral issues. "Preparation for exploration class space flight requires NASA to focus much more attention on human behavior," said the report.
"Alcohol is freely used in crew quarters," the report said. "Two specific instances were described where astronauts had been so intoxicated prior to flight that flight surgeons and/or fellow astronauts raised concerns to local on-scene leadership regarding flight safety. However, the individuals were still permitted to fly."
The panel said certification of astronauts for flight duty has no method to detect drinking episodes.
It also recommended NASA develop a code of conduct for astronauts.
"In general, astronauts are highly motivated to fly," the report stated. "Opportunities to fly in space are scarce and decreasing. The criteria for flight selection and how they are applied are unknown to the astronauts. Medical and behavioral health issues are perceived as having high potential for use to eliminate astronauts from mission assignment."
The drinking allegations shocked former astronauts and came as NASA deals with the apparent sabotage of a computer bound for the orbiting international space station.
Earlier two former shuttle astronauts told CNN that the drinking allegations, if true, would be "mind-boggling."
One of the astronauts said he was not aware of anyone "unduly using alcohol prior to launch." The other said "not a chance," and added that he would have "thrown the person off the crew."
The astronauts asked that they not be named because of the sensitive nature of the allegations.
Former NASA flight surgeon Jonathan Clark told CNN he'd never heard such reports in the past, although he said he had seen crew allowed to fly while "extremely tired" from "pre-mission fatigue." "Many of them took sleeping pills to try get some normal sleep state, and there were times when crew were groggy."
He said there are traditional pre-flight celebrations and toasting with crew members and their families, "but the times I've been involved ... there was beer and wine but there wasn't any heavy drinking."
Clark said he attended many such events as a flight surgeon or as an astronaut spouse. Clark's wife Laurel Clark was killed along with six other astronauts in the 2003 Columbia disaster.
NASA's next scheduled space shuttle mission is August 7, for the crew of the orbiter Endeavour. A NASA spokesman said an internal investigation has been launched into the sabotage of the computer and said it would be repaired and ready for next month's liftoff.
The computer problem surfaced, NASA said, when a subcontractor who supplied the computer notified NASA. Workers checked the computer and found it was intentionally damaged.
The computer is to be installed aboard the station's U.S. laboratory to monitor sensors on the facility's truss, NASA said. It was not designed to be part of any command and control or navigation functions, he said. E-mail to a friend
CNN's John Zarrella contributed to this report.